This invention relates to an improved bracket for holding electrical wire on ceilings, floors, and other construction members.
As buildings are constructed, electrical wiring is run from a circuit breaker panel out to the various outlets, switches, and equipment being used in the building. In the past, wiring cable has often been stapled to building members such as floor joists, vertical studs, or ceiling joists or rafters. Bundles of wire so stapled often become very confusing making it hard to trace individual circuits, or to present a clean, professional look to the finished job when many of the runs are just a mass of individual wires.
In addition, the National Electrical Code (NEC) requires that if wires are stapled to a piece of wood, such as a floor joist, the thickness of the wood has to be at least 1 and 1/4 inches to preclude someone from nailing through the wood and hitting a wire stapled on the opposite side of the wood. When sawed beams were used for floor joists, the beam width usually exceeded these specifications, but with the advent of the prefabricated, wooden "I" beams, used for floor joists and the like, wire stapled on one side of the "I" beam is only about a 1/2 inch away from the opposite side of the "I" beam. Nailing or screwing through such an "I" beam and striking a wire stapled to the other side could cause a serious electrical shock or cause a fire to start. A need exists for a bracket which can be mounted to the web of a wooden "I" beam to hold electrical wire at least the spacing required by the Electrical Code, from the opposite side of the web.
Also during construction, available space for running wires is greatly reduced as other crafts such as plumbing, heating, ventilation, sprinkler piping, and vacuum systems run their materials in the same joist cavity. Thus, a need arises for a bracket to organize wiring to effectively utilize the space in such cavity.
Furthermore a need exists for individual brackets which are designed to be smoothly broken into separate sections along a breakaway line so that an installing electrician need not carry a great many different sizes of wire brackets. The sections broken away should have the appropriate dimensions to fit different sizes of prefabricated "I" beams as well as having the appropriate flanges or plates to permit installing them with different orientations on the various building members.
Further, a need exists for a bracket having indexing fingers which would enable an installing electrician to properly position a bracket on top of a ceiling joist used in roof trusses.
In the early days of running electrical wires in buildings, a bracket, having a longitudinal series of holes, was used to separate the individual wires--see U.S. Pat. No. 934,463 to Ritter. These brackets, which were positioned adjacent to a ceiling, were mounted using screws positioned at right angles to the wires running through the bracket. The brackets in this patent had no flexibility to be mounted along any of the other axes, or to be broken into smaller portions.
U.S. Pat. No. 3,022,030 to Geer illustrates another bracket that can be mounted between joists, but this bracket uses open-mouth hangers to hold wire. Open mouth hangers do not provide a positive method for stringing wire where the wire will remain in the position so strung.
Other patents, such as U.S. Pat. No. 2,419,675 to Carpenter, and U.S. Pat. No. 5,060,892 to Dougherty illustrate other hangers, but these hangers mount in only one position where the hanger is essentially horizontal.
From the above, it can be seen that a considerable improvement can be brought to the electrical wiring trades if a bracket can be made which can be secured to construction members in any one of three axes of the bracket (length, width, or depth). The bracket should have holes to run wire through so that, once installed, the wire can not be easily moved. In addition, the bracket should be capable of being broken into smaller portions to provide on-site flexibility for an electrician to fit the brackets to appropriate construction members along the entire run of the wire. Further, this bracket should have indexing fingers to enable an installer to properly install the bracket on top of joists such as ceiling joists.